Rotary motor

ABSTRACT

A rotary vanes type motor having a plurality of vane mounted for reciprocal movement in a housing in a radial direction with respect to a shaft journalled in the housing. A piston member is eccentrically mounted on the shaft in the housing so that the piston member will orbit without rotation in the housing as the shaft rotates. The vanes are connected to the piston member so as to reciprocate when the piston member orbits. The housing, vanes, and piston member defining a plurality of chambers to which a working fluid may be admitted in sequence to induce orbiting of the piston member and resulting rotation of the shaft.

This invention relates to a rotary motor which may be operated on theinternal combustion engine principle, but may also operate as a steamengine or hydraulic motor.

There have been proposed numerous constructions of rotary motors, manyincorporating sliding vanes which divide a cavity formed between astationary and rotary member into a plurality of chambers. A commonproblem encountered in previously proposed vane-type rotary motors, isthe provision of adequate support for the sliding vanes, and themaintaining of an effective seal between the sliding vanes and thestationary housing and rotor. It has been the practice to support thevane for reciprocating sliding movement either in the stationary housingor in the rotor, with the projecting portion of the vane completelyunsupported. Suitable spring devices are provided to urge the vanes in adirection to maintain engagement between the free end of the vane andthe rotor or housing as the case may be.

One principal disadvantage of these constructions is that the vane isonly supported at one end and thus, when the vane is in its extendedposition, it is subjected to substantial bending stresses. In order towithstand these stresses it has been necessary to use vanes ofsubstantial thickness and hence of increased weight. The weight of thevanes introduces inertia problems and consequently necessitate strongspring devices to induce the necessary movement in the vanes to maintaincontact at their free end with the co-operating rotor or housing. Alsodeflection of the vane due to only one end being supported causesincreased frictional resistance to sliding movement of the vane.

It is the principal object of the present invention to provide a rotarymotor of the vane-type, in which the supporting and sealing problemsinherent in previously proposed vane-type rotary motors aresubstantially reduced to provide an effective motor.

With the above stated object in view, there is provided an enginecomprising a housing having a cavity defined by an internal peripheralwall and opposed end walls, a shaft rotatably supported in the housing,a piston member journalled eccentrically on said shaft to describe anorbital path within the cavity upon relative rotation between the shaftand housing, a plurality of vanes disposed radially to and spacedequally about the shaft axis and supported in the housing for reciprocalmovement radially with respect to the shaft axis, said vanes beingconnected to the piston member so that the piston member can moverelative to each vane in a direction at right angles to the direction ofreciprocation of the respective vane and at right angles to the shaftaxis to permit orbiting of the piston member upon reciprocation of thevanes relative to the housing, sealing means operatively disposedbetween each vane and the piston member, the housing peripheral wall andthe housing end walls to divide the cavity into a plurality of chambersthe volume of each chamber varying as the piston member orbits, andmeans to regulate the admission to and exhausting from each chamber insequence of a working fluid to induce orbiting of the piston member andresultant rotation of the shaft.

As the piston member describes a purely orbital movement, there is noangular movement between the vanes and the piston member, andconsequently the vanes may be connected to the piston member.Accordingly, it is not necessary to provide any spring devices to inducethe reciprocating movement of the vanes as this is positively induced bythe connection between the vanes and piston member.

The orbital movement of the piston member within the cavity of thehousing is such that the piston member maintains a constant angularrelation to any diametral plane passing through the shaft axis.

As the vanes are only subjected to pure reciprocal movement relative tothe housing each vane may be slidably supported in respective radialslots in each end wall and peripheral wall of the cavity.

Thus there is provided an engine comprising a housing having a generallycylindrical cavity defined by a peripheral wall and opposed end walls, ashaft rotatably supported in the housing coaxial with the cavity, apiston member disposed within the cavity and journalled eccentrically onsaid shaft to describe an orbital path about the shaft axis when theshaft rotates, a plurality of vanes disposed radially to and spacedequally about the shaft axis, each vane being slidably supported inrespective slots in each wall and the peripheral wall for reciprocalmovement radially with respect to the shaft axis, each vane beingconnected to the piston member to reciprocate relative to the housingupon orbiting of the piston member to the housing, sealing meansoperatively disposed between each vane and the piston member, thehousing peripheral wall and the housing end walls to divide the cavityinto a plurality of chambers, the volume of each chamber varying as thepiston member orbits, and means to regulate the admission to andexhausting from each chamber in sequence of a working fluid to induceorbiting of the piston member and resultant rotation of the shaft.

The supporting of the vanes in the slots in the end walls of the chambersubstantially reduces the stresses in the vanes, particularly when theyare in their extended position, and thus the vanes will not bend ordeflect, and may be made of a lighter construction with a resultantreduction in inertial loads.

Some further advantages inherent in this construction are:

1. There is no contact between the peripheral surfaces of the pistonmember and the chamber, and thus accurate machining of these surfaces isnot necessary, and there is no wearing thereof.

2. The pressure differential on the opposite sides of the vanes, at anypoint in their working cycle, is small in comparison with many othervane type engines. The maximum pressure differential occurs when thevane is retracted to its fullest extent, and hence has a minimum areaexposed to the pressure difference.

3. The surfaces of the vanes which are in wearing contact with thepiston member or housing may be flat surfaces, and thus uniform wear onthese surfaces does not interfere with their functioning. The flatsurfaces also simplify seal construction as flat seal strips may beused.

4. Lubrication and cooling of the vanes may be simply effected by an oilspray directed onto the face of the vanes when in the retracted positionas substantially the whole surface of the vane is then outside theworking chamber. Further, the incoming charge of gas will contact alarge exposed surface of the vane as the vane is in its fully extendedposition.

Conveniently there is provided at least one member having two journalledsections eccentric with respect to one another, one rotatably supportedin the housing and the other in the piston member with the axes thereofparallel to the shaft axis, the eccentricity of the journalled sectionsand the location thereof relative to the shaft being such as to guidethe piston member in the orbital path when the shaft rotates. Preferablythere are three such members spaced equally about the shaft axis.

The invention will be more readily understood from the followingdescription of an internal combustion engine as illustrated in theaccompanying drawings. The engine illustrated operates on the two-strokecycle, but it will be readily understood that by the provision ofsuitable valve mechanisms, the engine may operate on the four-strokecycle. Similarly, it will be readily understood that with appropriatemodification, the engine may operate as a steam engine or hydraulicmotor.

Referring now to the drawings:

FIG. 1 is a section view of the engine along a diametral plane.

FIG. 2 is a perspective view with the exhaust end cover and chamber endplates removed to show the cam member and vanes.

FIG. 3 is a perspective view similar to FIG. 2 with the vane and cammember also removed.

FIG. 4 is an enlarged sectional view of portion of the housing and cammember showing the arrangement of seals for one vane.

The engine comprises a cylindrical outer casing 10, opposed end coverplates 11, 11a attached by bolts 12 around their periphery to the outercasing 10. Bearings 15 supported in the cover plates rotatably supportthe crank shaft 16 for rotation about an axis co-axial with the outercasing 10.

The six arcuate peripheral combustion chamber sections 18 are disposedwithin the outer casing 10 in a generally circular formation co-axialwith the shaft 16. The chamber sections 18 have cavities 19 formedtherein which constitute a cooling water jacket. The arcuate length ofthe chamber sections 18 is such that when assembled slots 20 areprovided between adjacent sections 18, the slots 20 extending the fullaxial and radial dimension of the sections and radially with respect tothe crank shaft. The six chamber sections define an internal surface ofgenerally hexagonal shape with the corners of the hexagon rounded by acurved surface which blends smoothly with the adjacent straight sides.

Associated with each of the chamber sections 18 are two opposed chamberend plates 24, 25, of generally sector shape, which extend from theouter casing 10 to the vicinity of the crank shaft 16. The chamber endplates 24, 25 also define between adjacent radial faces, radial slots 27which register with the slots 20 defined by the chamber sections 18. Theouter peripheral edge 28 of the chamber end plates are received in therecess 29 in the outer casing 10 and the end cover plates 11, 11a,chamber sections 18 and chamber end plates 24, 25, and held in assemblyby the bolts 12 extending through aligned apertures therein and thelocating dowels 31.

Two parts spherical combustion cavities 35 are provided in the internalperipheral surface of each chamber section 18, with a threaded sparkplug aperture 36 communicating with one of each cavities. Associatedwith each spark plug aperture 36 is a sleeve 37 extending between thechamber section 18 and the outer casing 10 to house, and provide access,to the spark plug.

The crank shaft 16 has the piston member 40 mounted on the eccentricjournal 17 of the crank shaft through the bearings 21 to permit relativeangular movement therebetween. The piston member 40 comprises theperipheral ring and integral side plate 42, and attached side plate 43,with six equally spaced slots 45 in each side plate. The slots 45 ineach side plate are arranged in the formation of a hexagon having anaxis coincident with the axis of the eccentric journal 17 of the crankshaft. Corresponding slots 45 in the respective side plates 42, 43 arein alignment in the axial direction.

The three eccentrics 50 are supported in bearing 52 in the inlet endcover plate 11 in equally spaced relation about the axis of the crankshaft and engage apertures 51 in side plate 43 of the piston member 40.The throw of the eccentrics 50 are arranged in relation to that of thecrank shaft so that when the crank rotates the piston member describesan orbital path. The orbital path is such that the slots 45 retain acontstant angular relation to any radial plane passing through the axisof the crank shaft 16. Annular seal rings 60, located in respectivegrooves 61 in each side plate of the piston member, are pressed againstthe chamber end plates by the respective spring strips below the sealrings.

The crank shaft 16 is of two-piece construction whereby the web 21 andjournal 22 may be detached from the eccentric journal 17 to permitassembly of the piston member 40 to the journal 17. The counter-weight32 has an integral cylindrical mounting portion 33 rotatably supportedon the spigots 26 on the respective side plates of the piston member.The counter-weight is disposed diametrically opposite the eccentricjournal 17 of the crankshaft and is caused to rotate with the crankshaftby the pin 93 engaging the slot 94 in the counter-weight. Thecounter-weight is made of bronze so that the bearing bushes are notrequired. This arrangement of the counter-weight provides both staticand dynamic balance. The vanes 70 are of generally rectangular shape andare supported in the slots 20 and 27 for sliding movement in the radialdirection relative to the crank shaft 16. Each vane 70 is connected tothe piston member 40 by two legs 72 extending along each radial edge ofthe vane and secured to the vane by studs 74. The laterally projectingpin 76 at the inner end of each leg is received in a slipper 92 whichslidably engages the respective slots 45 in each side plate of thepiston member so that the vanes reciprocate in response to orbitalmovement of the piston member 40. The seal strip 73 located in therecess 75 in the radially inner edge of the vane engages the outerperpheral surface 46 of the piston member. The spring strip 62 below theseal strip 73 maintains the latter in engagement with the peripheralsurface 46.

It will be noted that the portions of the peripheral surface of thepiston member along which the respective vanes move are flat andparallel to the associated slots 45 in the side plate. The peripheralsurface of the piston member 40 is thus of generally hexagonal shapewith the corners rounded.

Seal strips 77 and associated spring strip 78 are provided in radiallyextending grooves 79 in each side face of each vane, adjacent each endthereof. The seal strips 77 engage the walls of the radial slots 27formed between the chamber end plates 24, 25.

Further seal strips 80 and associated spring strips 81 are provided ingrooves 82 in each end face of the arcuate chamber sections 18 to engagethe opposite side faces of each vane.

The construction so far described provides sic chambers defined by thearcuate sections 18, the chamber end plates 24, 25 the vanes 70, and thepiston member 40. During each complete cycle of orbital movement of thepiston member the volume of each chamber undergoes a complete cycle ofvariation from minimum to maximum and return to minimum. It will be thusunderstood that the application of a fluid under pressure to eachchamber in sequence when the chamber is at or near minimum volume willapply a force to the portion of the piston member of the chamber toinduce orbital movement of the piston member 40 and resultant rotationof the crank shaft 16.

The following description relates to the further details of constructionshown in the drawings relevant to an internal combustion engine but itwill be readily understood by those skilled in the art the nature ofmodification necessary in order to operate the engine by the use ofother working fluids such as steam or hydraulic fluid.

Referring again to the drawings, inlet ports 85 extend through the endcover plate 11 and the respective chamber end plates 24 to communicatewith the respective chambers. The ports 85 are opened and closed by thepiston member 40 during the orbital movement thereof. Similar exhaustports 88 are provided in the opposite end cover plate 11a and chamberend plates 25, and are likewise opened and closed by the piston member40. It will be noted that three of the inlet ports 85 are in thevincinity of the bearings 52 supporting the eccentrics 50.

Each inlet port 85 communicates with the inlet manifold 90 and allexhaust ports 88 communicate with the exhaust manifold 91.

This porting arrangement allows the engine to operate on the two strokecycle, and the actual shape and location of the ports may be readilydetermined by those skilled in the art.

As the two stroke cycle does not provide suction to draw the mixtureinto the chamber, a suitable blower (not shown) is provided to deliverthe mixture to the inlet manifold 90 communicating with each inlet port85. The blower may be driven by the crank shaft 16 or may be an exhaustdriven turbo-blower. The fuel may be supplied by a conventionalcarburetor or a fuel injection system may be used. It will beappreciated that the engine may also operate on the diesel principle,either two or four stroke cycle.

If the engine is to operate on the four stroke cycle inlet and exhaustports may be provided in the arcuate peripheral chamber section 18 withmechanically or other suitably operated valves to control the admissionand exhaust of the charge to each chamber.

A feature of this engine is that the rate of increase in volume of eachchamber relative to the angular movement of the crank shaft is notuniform, the rate being initially high. In the engine shown in thedrawings the volume of each cylinder increases to approximately 68percent of maximum volume during the initial 90° of rotation of thecrank shaft from top dead centre. This results in a high torque at lowengine revolutions.

The engine shown in the drawings has provision for the fitment ofconventional spark-plugs and these would be energised in sequence by aconventional magneto or coil and distributor ignition system. If theengine operated on the diesel principle, a suitable injector would befitted to as a substitute for the spark-plug.

In order to reduce the loading on the connections between the vanes andthe orbiting piston member the gallery between the outer casing 10 andthe chamber sections 18, may be filled with a liquid such as oil, as thevanes are moved in a radially outward direction by the orbiting pistonmember, the oil displaced by the outwardly moving vanes will impart acorresponding radially inward movement to other vanes and consequentlythe inwardly directed force applied by the piston member to the inwardlymoving vanes will be reduced. Alternatively, or in addition, the ends ofthe vanes adjacent the piston member may have surfaces projectinglaterally therefrom within the engine chambers, so that the fluidpressure in the chambers will apply a force to the vanes to move them ina radially inward direction.

I claim:
 1. An engine comprising a housing having a cavity defined by aninternal peripheral wall and opposed end walls; a shaft rotatablysupported in said housing; a piston member journalled eccentrically onsaid shaft to describe an orbital path within said cavity upon relativerotation between said shaft and housing; a plurality of vanes disposed.[.radially to and spaced equally.]. about the axis of said shaft andsupported in said housing for reciprocal movement .[.radially.]. withrespect to said shaft axis, each of said vanes being connected to saidpiston member so that said piston member can move relative to each vanein a direction at right angles to the direction of reciprocation of therespective vane and at right angles to said shaft axis to permitorbiting of said piston member upon reciprocation of said vanes relativeto said housing; .Iadd.a plurality of flat faces on the periphery of thepiston member, the radially inner face of each vane engaging arespective flat face on the piston member parallel to the direction ofrelative movement between the vane and the piston member throughout theextent of said movement; .Iaddend.sealing means operatively disposedbetween each of said vanes and said piston member, said housingperipheral wall and said housing end walls to divide said cavity into aplurality of chambers, the volume of each chamber varying as said pistonmember orbits; and means to regulate the admission to and exhaustingfrom each of said chambers in sequence of a working fluid to induceorbiting of said piston member and resultant relative rotation betweensaid shaft and housing.
 2. An internal combustion engine comprising ahousing having a cavity defined by an internal peripheral wall andopposed end walls; a shaft rotatably supported in said housing; a pistonmember journalled eccentrically on said shaft to describe an orbitalpath within said cavity upon relative rotation between said shaft andhousing; a plurality of vanes disposed .[.radially to and spacedequally.]. about the axis of said shaft and supported in said housingfor reciprocal movement .[.radially.]. with respect to said shaft axis,each of said vanes being connected to said piston member so that saidpiston member can move relative to each vane in a direction at rightangles to the direction of reciprocation of the respective vane and atright angles to said shaft axis, whereby orbiting of said piston membereffects reciprocation of said vanes relative to said housing; .Iadd.aplurality of flat faces on the periphery of the piston member, theradially inner face of each vane engaging a respective flat face on thepiston member parallel to the direction of relative movement between thevane and the piston member throughout the extent of said movement;.Iaddend.sealing means operatively disposed between each of said vanesand said piston member, said housing peripheral wall, and said housingend walls to divide said cavity into a plurality of chambers, the volumeof each chamber varying as said piston member orbits; and means toregulate the admission to, ignition in and exhausting from each of saidchambers in sequence of a gaseous mixture to induce orbiting of saidpiston member and resultant relative rotation between said shaft andhousing.
 3. An internal combustion engine as claimed in claim 2, whereineach of said vanes is slidably supported in respective slots in each ofsaid end walls and said peripheral wall of said housing.
 4. An internalcombustion engine as claimed in claim 2, further comprising at least onemember having two journal sections eccentric with respect to oneanother, one of said sections rotatably supported in said housing andthe other of said sections rotatably supported in said piston member,with the axis of each section parallel to said shaft axis, theeccentricity of said journal sections and the location thereof relativeto said shaft being such as to guide said piston member in the orbitalpath when said shaft rotates.
 5. An internal combustion engine asclaimed in claim 2, wherein each of said vanes has a radially inwardlyextending portion at each axial end thereof, each said portion beingconnected to said piston member to prevent relative movement betweensaid vane and piston member in the radial direction and to permitrelative movement therebetween in a direction at right angles to thedirection of reciprocating movement of said vane. .[.6. An enginecomprising a housing having a generally cylindrical cavity defined by aperipheral wall and opposed end walls; a shaft rotatably supported insaid housing coaxial with said cavity; a piston member disposed withinsaid cavity and journalled eccentrically on said shaft to describe anorbital path about the axis of said shaft when said shaft rotates; aplurality of vanes disposed radially to and spaced equally about saidshaft axis, each of said vanes being slidably supported in respectiveslots in each of said end walls and said peripheral wall for reciprocalmovement radially with respect to said shaft axis; each of said vanesbeing connected to said piston member to reciprocate relative to saidhousing upon orbiting of said piston member relative to said housing;sealing means operatively disposed between each of said vanes and saidpiston member, said housing peripheral wall, and said housing end wallsto divide said cavity into a plurality of chambers, the volume of eachchamber varying as said piston member orbits; and means to regulate theadmission to and exhausting from each of said chambers in sequence of aworking fluid to induce orbiting of said piston member and resultantrotation of said shaft..]. .[.7. An engine as claimed in claim 6,further comprising at least one member having two journal sectionseccentric with respect to one another, one of said journal sectionsrotatably supported in said housing, and the other of said journalsections rotatably supported in said piston member with the axis of eachsection parallel to said shaft axis, the eccentricity of said journalsections and the location thereof relative to said shaft being such asto guide said piston member in the orbital path when said shaftrotates..]. .[.8. An engine as claimed in claim 6, wherein said pistonmember has an external peripheral surface including a plurality of flatsections spaced equally about the axis of said piston member, andextending the full width of said piston member in the axial directionthereof, said flat sections sealably engaging with the radially innerend of one of said vanes and extending in a plane normal to thedirection of reciprocation of the respective vane..].
 9. An engine asclaimed in claim .[.6.]. .Iadd.3.Iaddend., wherein each of said vaneshas a radially inwardly extending portion at each axial end thereof,located in said respective slots in each of said end walls, each of saidportions being connected to said piston member to prevent relativemovement between said vane and piston member in the radial direction andto permit the relative movement therebetween in the direction at rightangles to the direction of reciprocation of said vane. .[.10. An enginecomprising a housing having a generally cylindrical cavity defined by aperipheral wall and opposed end walls; a shaft rotatably supported insaid housing coaxial with said cavity; a piston member disposed withinsaid cavity and journalled eccentrically on said shaft to describe anorbital path about the axis of said shaft when said shaft rotates; aplurality of vanes disposed radially to and spaced equally about saidshaft axis, each of said vanes being slidably supported in respectiveslots in each of said end walls and said peripheral wall for reciprocalmovement radially with respect to said shaft axis, said vanes beingindependently connected to said piston member so that said piston membercan move relative to each vane in a direction at right angles to thedirection of reciprocation of the respective vane and at right angles tosaid shaft axis to permit orbiting of said piston member uponreciprocation of said vanes relative to said housing; sealing meansoperatively disposed between each of said vanes and said piston member,said housing peripheral wall and said housing end walls to divide saidcavity into a plurality of chambers, the volume of each of said chambersvarying as said piston member orbits; and means to regulate theadmission to and exhausting from each of said chambers in sequence of aworking fluid to induce orbiting of said piston member and resultantrotation of said shaft..].
 11. An engine as claimed in claim .[.10.]..Iadd.3.Iaddend., further comprising at least one member having twojournal sections eccentric with respect to one another, one of saidjournal sections rotatably supported in said housing and the other ofsaid journal sections rotatably supported in said piston member with theaxis of each section parallel to said shaft axis, the eccentricity ofsaid journal sections and the location thereof relative to said shaftbeing such as to guide said piston member in the orbital path when saidshaft rotates. .[.12. An engine as claimed in claim 10, wherein saidpiston member has an external peripheral surface including a pluralityof flat sections spaced equally about the axis of said piston member,and extending the full width of said piston member in the axialdirection thereof, said flat sections sealably engaging with theradially inner end of one of said vanes and extending in a plane normalto the direction of reciprocation of the respective vane..].
 13. Anengine as claimed in claim .[.12.]. .Iadd.2.Iaddend., wherein each ofsaid vanes has a radially inwardly extending portion at each axial endthereof, each said extending portion of said vanes having a slippermember mounted thereon, said piston member having radial end walls ateach axial end thereof, and a pair of slots associated with each of saidflat sections of said peripheral surface, one of said slots in each ofsaid end walls, each of said slots extending parallel to the associatedflat section, said slipper members on each of said vanes slidablyengaging the respective slots to connect said vane to said piston memberto prevent relative movement between said vane and piston member in theradial direction and to permit relative movement therebetween in adirection parallel to said flat section of said piston member peripheralsurface with which the vane engages. .[.14. An engine as claimed inclaim 10, wherein each of said vanes has a radially inwardly extendingportion at each axial end thereof, located in said respective slots ineach of said end walls, each said portion being connected to said pistonmember to prevent relative movement between said vane and piston memberin the radial direction and to permit the relative movement therebetweenin the direction at right angles to the direction of reciprocation ofsaid vane..].
 15. An engine as claimed in claim .[.10.]..Iadd.2.Iaddend., wherein said piston member is hollow, and acounter-weight is mounted within said piston member and rotatablysupported by said piston member of rotation in unison with said shaftabout said shaft axis, said counter-weight being of a mass anddisposition relative to said shaft to statically and dynamically balancesaid shaft.